Steel A227
ASTM A227
A227 is hard-drawn, high-carbon steel spring wire (0.45–0.85 % C, cross-referenced to 1065–1075 and 65Mn), supplied in Class I and Class II tensile levels plus stress-relieved and zinc-coated variants.
Reference datasheet — A227 is not in the instant-quote catalog. Upload your part and an engineer will quote it in this grade or suggest the closest stocked equivalent.
Values for the CLI condition
A227 tempers and conditions
A227 is supplied in 3 conditions, soft to hard. CLI is the default FabDigit quotes; the values on this page are for it.
Compare all 3 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
CLIDefault Class I | Default general-purpose hard-drawn spring wire for moderate-stress static or low-cycle springs where cost matters. | 1,380 | 1,620 | 4 | 46 HRC | — |
Stress relieved | Standard post-coiling low-temperature bake that restores elastic limit, reduces set/relaxation and removes plating hydrogen; use for all finished springs. | 1,480 | 1,650 | 4 | 47 HRC | 9.5 % IACS |
Class II | Choose when a higher stress level or smaller spring index is required; tensile is roughly 10 % above Class I at the same diameter, with slightly less ductility for coiling. | 1,520 | 1,790 | 3 | 49 HRC | — |
Supply forms, finishes and certifications
Ways A227 is supplied — form, process route, surface or paperwork — without a datasheet of their own. The property values above apply.
| Option | What it is | Type |
|---|---|---|
ZN | Zinc-coated (galvanized) hard-drawn spring wire | Coating |
What is A227?
A227 is hard-drawn, high-carbon steel spring wire (0.45–0.85 % C, cross-referenced to 1065–1075 and 65Mn), supplied in Class I and Class II tensile levels plus stress-relieved and zinc-coated variants. It is the low-cost choice for general-purpose mechanical springs and wire forms, cold-coiled straight from the spool, with reference properties of 1380 MPa yield, 1620 MPa tensile, 4 % elongation and 46 HRC. Service is limited to 120 °C, corrosion resistance is minimal (score 10) and it is not intended for fatigue-critical duty. For cyclic or high-stress springs, use A228 music wire. A227 has a density of 7.85 g/cm³ (0.284 lb/in³), heavier than 56% of steel grades. It melts at 1,425°C (2,597 °F). A227 has a yield strength of 1,380 MPa (200 ksi) and a tensile strength of 1,620 MPa (235 ksi) — stronger than 96% of steel grades. Elongation at break is 4% and the elastic modulus is 200 GPa (29 Msi).
What is A227 used for?
- mechanical springs
- clips
- wire forms
- general-purpose coil springs
Advantages
- High strength — 1,380 MPa (200 ksi), better than 96% of steel grades
Limitations
- Limited service temperature — 120°C (248 °F), worse than 100% of steel grades
- Limited ductility — 4%, worse than 98% of steel grades
- Low fracture toughness — 35 MPa·√m (31.9 ksi·√in), worse than 94% of steel grades
- Difficult to machine — 25/100, worse than 93% of steel grades
- Difficult to weld — 15/100, worse than 91% of steel grades
A227 properties
Typical room-temperature values for A227-CLI; bars are the position among steel grades.
Physical3
A227 has a density of 7.85 g/cm³ (0.284 lb/in³), heavier than 56% of steel grades. It melts at 1,425°C (2,597 °F).
Mechanical15
A227 has a yield strength of 1,380 MPa (200 ksi) and a tensile strength of 1,620 MPa (235 ksi) — stronger than 96% of steel grades. Elongation at break is 4% and the elastic modulus is 200 GPa (29 Msi).
Thermal6
A227 is rated for continuous service to 120°C (248 °F). It conducts heat at 47 W/m·K (27.2 BTU/hr·ft·°F), better than 75% of steel grades. Thermal expansion is 12.2 µm/m·K (6.78 µin/in·°F).
Electrical3
A227 conducts electricity at 9 % IACS, better than 71% of steel grades.
Chemical & Environmental3
Corrosion resistance is not recommended (10/100), worse than 86% of steel grades.
Sustainability4
Producing a kilogram of A227 takes about 28 MJ of energy and emits 2.1 kg of CO₂ — less than 56% of steel grades. Typical recycled content is 25%.
Manufacturability7
A227's machinability is poor (25/100, worse than 93% of steel grades); weldability poor (15/100); formability fair (45/100).
Common Calculations5
Values are nominal handbook figures for design screening. Certified mill or lot data ships with every FabDigit order on request.
Strength versus weight in the steel family
Yield strength against density for every steel grade FabDigit runs. A227 is highlighted; hover a dot for its name, or open the interactive family chart.
Working with A227
Is A227 easy to machine?
Rarely machined — the drawn wire is hard and abrasive; grind, shear, or abrasive-cut ends rather than turn or drill.
Can A227 be welded?
Essentially unweldable in service condition: 0.45–0.85 % C gives a brittle martensitic HAZ; use mechanical hooks/loops or resistance-weld only with a controlled post-weld temper.
Can A227 be formed, bent or molded?
Cold-coiled on CNC spring formers straight from the spool; keep spring index ≥4, then bake 230–290 °C for 20–30 min to relieve coiling stresses and set the free length.
A227 chemical composition (wt %)
Limits by weight percent from the governing specification, written the way the spec states them — a single maximum for impurities, a range for alloying elements, and the base element as balance. Nominal is the typical mid-range value.
| Element | Spec limit (wt %) | Nominal |
|---|---|---|
| CASTM A227 heat analysis; the Chinese equivalent 65Mn sits at 0.62–0.70 % C | 0.45 – 0.85 | 0.65 |
| Mn65Mn: 0.90–1.20 % | 0.3 – 1.3 | 0.8 |
| P | ≤ 0.04 | 0.02 |
| S | ≤ 0.05 | 0.03 |
| Sitypical for 65Mn / silicon-killed rod; not always specified in A227 | 0.15 – 0.35 | 0.25 |
| Fe | balance |
What surface finishes work on A227?
Ship oiled or phosphated for indoor use; for corrosion service use mechanical zinc, hot-dip galvanize, or Zn-Ni plate with a post-plate hydrogen-relief bake at 190–220 °C within 4 h.
Surface treatments FabDigit runs on steel parts — pick them in the quote configurator or call them out on the drawing. Each links to its datasheet in the surface-finish library (thickness, specs, call-out, material verdicts).
Organic Coating
Black / Phosphate
Thermal Spray
Equivalent designations
Standards and trade names that resolve to Steel A227 in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.
- Similar grades
- 1065-107565Mn
How much does A227 cost?
A227 is a budget-cost steel ($), cheaper than about 90% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
A227 — frequently asked
What is A227 used for?
A227 is typically used for mechanical springs, clips, wire forms and general-purpose coil springs. In short: cheapest general spring wire; cold-coiled as drawn; not fatigue-rated.
What is the yield strength of A227?
A227 has a typical yield strength of 1,380 MPa (200 ksi) and a tensile strength of 1,620 MPa (235 ksi) — stronger than 96% of steel grades. Strength varies by condition: see the 3 listed tempers.
Is A227 easy to machine?
Not especially — machinability is rated poor (25/100, worse than 93% of steel grades). Rarely machined — the drawn wire is hard and abrasive; grind, shear, or abrasive-cut ends rather than turn or drill.
Can A227 be welded?
Not readily — weldability is rated poor (15/100). Essentially unweldable in service condition: 0.45–0.85 % C gives a brittle martensitic HAZ; use mechanical hooks/loops or resistance-weld only with a controlled post-weld temper.
What surface finishes work on A227?
Ship oiled or phosphated for indoor use; for corrosion service use mechanical zinc, hot-dip galvanize, or Zn-Ni plate with a post-plate hydrogen-relief bake at 190–220 °C within 4 h.
Can A227 be formed, bent or molded?
Cold-coiled on CNC spring formers straight from the spool; keep spring index ≥4, then bake 230–290 °C for 20–30 min to relieve coiling stresses and set the free length.
What is the maximum service temperature of A227?
A227 is rated for continuous use to about 120°C (248 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between A227-CLI and A227 CLII?
CLI is the default condition — default general-purpose hard-drawn spring wire for moderate-stress static or low-cycle springs where cost matters. CLII: choose when a higher stress level or smaller spring index is required; tensile is roughly 10 % above Class I at the same diameter, with slightly less ductility for coiling. Yield strength is 1,380 MPa in CLI versus 1,520 MPa in CLII.
How much does A227 cost?
A227 is a budget-cost steel ($), cheaper than about 90% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
Sources
- ASTM A227/A227M — Standard Specification for Steel Wire, Cold-Drawn for Mechanical Springs — ASTM International (2017)
- ASM Handbook Vol.1 — Properties and Selection: Irons, Steels, and High-Performance Alloys (Spring Steels) — ASM International (1990)
- Handbook of Spring Design — Spring Manufacturers Institute (SMI) (2013)
- ASTM A370 — Mechanical Testing of Steel Products (hardness conversions) — ASTM International (2022)
Property data is compiled from published supplier and standards handbooks and normalised for comparison; hardness values on non-Brinell scales are converted approximately for charting only. Manufacturability limits are FabDigit quote-engine defaults and may be relaxed by engineering review. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.